Добавление отступа/поля к Spannable

Вы можете использовать ReplacementSpan. В вашей деятельности:

TextView tagsTextView = (TextView) mView.findViewById(R.id.tagsTextView);
SpannableStringBuilder stringBuilder = new SpannableStringBuilder();

SpannableString tag1 = new SpannableString("9.5");
stringBuilder.append(tag1);
stringBuilder.setSpan(new TagSpan(getResources().getColor(R.color.blue), getResources().getColor(R.color.white)), stringBuilder.length() - tag1.length(), stringBuilder.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

SpannableString tag2 = new SpannableString("excellent!");
stringBuilder.append(tag2);
stringBuilder.setSpan(new TagSpan(getResources().getColor(R.color.blueLight), getResources().getColor(R.color.blue)), stringBuilder.length() - tag2.length(), stringBuilder.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
tagsTextView.setText(stringBuilder, TextView.BufferType.SPANNABLE);

TagSpan.java

public class TagSpan extends ReplacementSpan {
    private static final float PADDING = 50.0f;
    private RectF mRect;
    private int mBackgroundColor;
    private int mForegroundColor;

    public TagSpan(int backgroundColor, int foregroundColor) {
        this.mRect = new RectF();
        this.mBackgroundColor = backgroundColor;
        this.mForegroundColor = foregroundColor;
    }

    @Override
    public void draw(Canvas canvas, CharSequence text, int start, int end, float x, int top, int y, int bottom, Paint paint) {
        // Background
        mRect.set(x, top, x + paint.measureText(text, start, end) + PADDING, bottom);
        paint.setColor(mBackgroundColor);
        canvas.drawRect(mRect, paint);

        // Text
        paint.setColor(mForegroundColor);
        int xPos = Math.round(x + (PADDING / 2));
        int yPos = (int) ((canvas.getHeight() / 2) - ((paint.descent() + paint.ascent()) / 2)) ;
        canvas.drawText(text, start, end, xPos, yPos, paint);
    }

    @Override
    public int getSize(Paint paint, CharSequence text, int start, int end, FontMetricsInt fm) {
        return Math.round(paint.measureText(text, start, end) + PADDING);
    }
}

Вы можете использовать RoundedBackgroundSpan.

1. Он поддерживает как padding, так и margin
2. Это позволяет избежать ситуации, когда текст не центрирован в TextView.

3. Он также может установить BackgroundColor для текста.

   public class RoundedBackgroundSpan extends ReplacementSpan {
   
   
   private final int mBackgroundColor;
   private final int mTextColor;
   private final int mPaddingLeft;
   private final int mPaddingRight;
   private final int mMarginLeft;
   private final int mMarginRight;
   
   /**
    * Add rounded background for text in TextView.
    * @param backgroundColor background color
    * @param textColor       text color
    * @param paddingLeft     padding left(including background)
    * @param paddingRight    padding right(including background)
    * @param marginLeft      margin left(not including background)
    * @param marginRight     margin right(not including background)
    */
   public RoundedBackgroundSpan(int backgroundColor, int textColor,
                                int paddingLeft,
                                int paddingRight,
                                int marginLeft,
                                int marginRight) {
       mBackgroundColor = backgroundColor;
       mTextColor = textColor;
       mPaddingLeft = paddingLeft;
       mPaddingRight = paddingRight;
       mMarginLeft = marginLeft;
       mMarginRight = marginRight;
   }
   
   @Override
   public int getSize(Paint paint, CharSequence text, int start, int end,
                      Paint.FontMetricsInt fm) {
       return (int) (mMarginLeft + mPaddingLeft +
               paint.measureText(text.subSequence(start, end).toString()) +
               mPaddingRight  + mMarginRight);
   }
   
   @Override
   public void draw(Canvas canvas, CharSequence text, int start, int end, float x, int top, int y,
                    int bottom, Paint paint) {
       float width = paint.measureText(text.subSequence(start, end).toString());
       RectF rect = new RectF(x + mMarginLeft, top
               - paint.getFontMetricsInt().top + paint.getFontMetricsInt().ascent
               , x + width + mMarginLeft + mPaddingLeft + mPaddingRight, bottom);
       paint.setColor(mBackgroundColor);
       canvas.drawRoundRect(rect, rect.height() / 2, rect.height() / 2, paint);
       paint.setColor(mTextColor);
       canvas.drawText(text, start, end, x + mMarginLeft + mPaddingLeft,
               y - paint.getFontMetricsInt().descent / 2, paint);
   }
   }